The objective of this research program is to elucidate, at the molecular level, the mechanism and function of copper and zinc binding in the prion protein (PrP) and the relationship of these interactions to neuron maintenance and neurological disease. A misfolded form of the prion protein (PrP) is responsible for a class of fatal neurodegenerative diseases termed the Transmissible Spongiform Encephalopathies (TSEs), which include mad cow disease and Creutzfeldt-Jakob disease in humans. PrP is a highly abundant, membrane-bound glycoprotein found in all mammals and avian species. Although originally recognized for its role in neurodegenerative disease, it is now clear that PrP is essential for sustaining neuron function and regulating apoptosis. PrP takes up both copper and zinc at sites are essential for PrP activity. Over the last funding period, the PI's laboratory characterized structural and thermodynamic features of these metal ion sites and also identified a remarkable link between certain mutations and onset age in inherited prion disease. The next funding period will build on these findings using both magnetic resonance and cellular studies with the following projects: 1) determine the structure of the full-length, copper or zinc occupied protein; 2) evaluate how metal ions influence in vivo cleavage, implicated in apoptosis regulation; and 3) examine how structure and cellular behavior is altered by mutations associated with inherited disease, and also by mutations that prevent disease. Moreover, project three will apply new synthetic strategies for investigating the role of protein glycosylation. It is anticipated that these studies will provide fundamental new concepts for understanding the role of both PrP and copper in basic neurochemistry, and strategies for treating neurodegenerative disease and brain trauma.